[quote=@Liotrent]
<Snipped quote by Zarkun>

Yeah, that's mostly due to their great harass units, the zergling is one, early banes, maybe the odd muta harass. Zerg also expand like crazy while they do it, that's probably why Terran and Protoss have such a hard time keeping up.
[/quote]

I've seen Terran win ZvT matches, just not often.